问题 选择题

植食性动物家兔适于消化植物纤维的特殊结构是

A.发达的门齿

B.发达的盲肠

C.体内有膈

D.心脏有四腔

答案

答案:B

题目分析:与家兔的草食性相适应,家兔的牙齿分为门齿和臼齿,无犬齿,门齿长在上下颌的中央部分,形状像凿子,适于切断食物;臼齿长在上下颌的两侧,有宽阔的咀嚼面,适于磨碎食物;家兔的消化管很长,并且有特别发达的盲肠,消化食物的面积很大,适于消化植物纤维,而体内有膈和心脏四腔与食性无关。A. 门齿长在上下颌的中央部分,形状像凿子,适于切断食物,但不属于特殊结构,故A错误;B. 有特别发达的盲肠,消化食物的面积很大,适于消化植物纤维,属于家兔的特有,故B正确;C.体内有膈是哺乳动物的特征,不是家兔特有,故C错误;D.心脏有四腔是鸟类和哺乳类的特征,不是家兔特有的,故D错误。

单项选择题

After winning a big game, athletes are often asked how they feel. Usually athletes say how (1) it is to win this big game. On the contrary, the fact is that losing a big game, or in my case, all the games, can be even harder.
From the spectators’ point of view, last year’s basketball (2) for my high school team was nothing (3) of an embarrassment. And (4) 0 and 20 is certainly nothing to be proud of, that season had a bigger impact on me than any other. As a team captain, I knew it probably wouldn’t be the (5) year, but did I ever think we would lose every game Of course not. Since six of our top players had graduated, it was clear that we were a (n) (6) team who would struggle. The struggle began earlier than expected, (7) , as our team center was suspended (禁赛) for the season, and two key members decided to (8) for some reason. At this point, dropping out probably passed through every player’s mind, but in the end, we all stuck if out, (9) to work still harder.
Then there came a time when even our (10) and given up on us. Personally, I felt like it was (11) worthwhile giving my all. I thought, if even the coach doesn’t believe in us, why should I But just as my hope began to (12) , a teammate called a meeting. He said," Nobody thinks we are going to win, but, as teammates and friends, we (13) it to each other to go all out every game. "
It was that moment that (14) me how to be a leader. It hit me that I certainly didn’t (15) the role. As a leader you can never quit (16) the team who looks up to you. It is one (17) to be named captain, feel great and go through the motions, but it is quite another to be a real captain and make sure everyone realizes their full (18) all the time.
I am sure it is great to go through without losing and bringing home awards. But in all honesty, I (19) the fact that my team lost every game last year. It may not help me to become a better basketball player, but it already has made me a better leader, and (20)

A.with
B.alongside
C.on
D.for

判断题